Locomotive-drifting-valve mechanism.



F. W. MARTIN & J. L. MOHUN.

LOGOMOTIVE DRIFTING VALVE MECHANISM. APPLIOATIONTILED JULY30, 191s.

- 1,0 0,290, V BatentedDec.2,19I3.

- 2 SHEETSSHEET 1.

F. MARTIN & J. L.'MOHU N LOOOMOTIVE DRIFTING VALVE MECHANISM.

' APPLICATION FILED JULY 30, 1913. I 1,080,290. Patented Dec. 2, 1913.

I f G- 2 SHEIF'jfS-SHEET 2. 11 |||m p|nugmm Y an um I wrrnzsss v INVENTORS (\YWW W m FREDERICK W. MARTIN, on NEW YORK, AND :ronn L. Manon, or nnoonrnm, NEW YORK, ASSIGNORS or ONE-THIRD T ALBERT e. ELvIN, or soMEnvILLE, NEW

JERSEY.

1,oso,29o.

Specification of Letters Patent.

Application filed my 30, 1913. Serial no. 781,944. a

. 7 To all whom it may concern:

- Be it known that we, FREDERIQKYV. Mine TIN and JOHN L. MOHUN, both citizens of the United States, and residents, respectively, of the borough of Manhattan, in the city, county, and State of New York, andof the borough of Brooklyn, in the county of Kings, State of New York, have invented a certain new, and useful Locomotive-Drifting-Valve Mechanism, of which improve ment the following is a specification.

This invention relates to valve mechanism for admitting a small amount of steam to the cylinders of locomotives when running with the throttle closed, for the-purpose of furnishing suflicient lubrication and preventing the formation of a vacuum by the movement of the engine pistons.

The principal object of our invention is to provide improved valve -mechanism of this character Which shall be of simple construction and operated automatically to be openwhen the engineis running with the throttle closed, but'to" be closed when the engine comes to a stop and whenever the engine is standing for any considerable length of time, as when in the round house.

In the operation of locomotives it is the practice of the engineer-before starting, to set the reverse lever at its extreme position giving the longest movement to the engine distribution valves and then, as the speed of the locomotive increases, to set the reverse lever up several notches to give the desired degree of cut-off for economical use'iof steam. The reverse lever is therefore usually set-in some such intermediate cut-off position at the time when the engineer closes the throttle and locomotive begins drifting, and is dropped to its extreme or corner position when the locomotive comes to a stop, preparatory to starting again. When standing for a considerable period oftime it is customary to set the reverse lever in its central position.

According to our improvement, therefore, the drifting valve is controlled by the move.-

ment of the reverse gear of the locomotive,- it being preferably open when the reverse.

mechanism is at or between certain degrees of cut-0E, and closed when the reverse lever is dropped to its extreme position or raised to its central position.

In a locomotive using saturated steam for the engine there is, of course, no objection in having the drifting valve mechanism open to admit a small additional amount of saturated steam to the cylinders at the time that the engine is running with the throttle open,

but in engines using superheated steam the introduction of this small quantity of saturated steam through the drifting valve into the cylinders at the time superheated steam is being admitted to run the engine may be objectionable, and another feature of our improvement comprises means/for preventing the admission of saturated steam through the drifting valve mechanism when the engine is running with the throttle open and using superheated steam.

The improvement claimed fully set forth.

In the accompanying drawings, Figure 1 is a side elevation of a locomotive showing one application of our improvement; Fig. 2, a detail view upon a larger scale showing the valve device in vertical section; and Fig. 3, a detail view illustrating a modification.

According to the construction shown in the drawings the valve device comprises a casing 1, containing a valve 2, having a stem 3 extending outside the casing, said valve controlling communication from the pipe 4, leading from the boiler turret 5, to the pipe 6, and to the valve chests and cylinders of the engine. Any suitable means controlled by the movement of the reverse gear may be employed for 'operating said valve, as for instance, a camsector 7 mounted on the usual reverse shaft 8, which is operated by the arm 9, reach rod 10, and reverse lever 11, in the usual manner. The cam sector is provided With a recess 13 at its central portion between the two raised portions 15, and 15, which are adapted to engage the valve stem and raise the'valve 2, from its seat when the sector .and reverse shaft are turned in eitherv direction to the intermediate cut-off positions. When the shaft and sector are turned to the extreme position in either direction as indicated in dotted lines Fig. 2, the corner of the sector clears the valve stem and permits the valve is hereinafter Patented Dec. 2, 1913.

- vantage as alarger amount of lubrication is needed at that time. If desired-the length a reciprocating movement and may be connected .to be operated from the reverse gear at any desired point. Either of these constructions are adapted to be'used with either a manually operated'reverse gear or a power reverse gear, as will be readily understood.

When the reverse lever is set to the corner or extreme position, either forward or backward, the valve 2, will be held closed by the pressure of steam throu h pipe 4, but as the lever is set up to one of its lntermediate cutoil positions the cam portion 15, engages the valve stem and o ens the valve 2. Then when the throttle 1s closed and the locomo-' tive continues running, or drifting, with the reverse lever'in this position a limited quantity of saturated steam from the turret flows through the pipes 4 and 6 to the valve chests and cylinders of the engine, thus maintaining suflicient lubrication and preventing the carbonization of .oil and the formation of vacuum in the cylinders. When the reverse lever is then dropped to thecorner position a the locomotive comes to astop the valve is automatically closed thus stopping further flow of steam to the cylinders. When the locomotive is left standing for any material length of time; as when in the roundhouse, the reversing lever is normally set in its central position in which the drifting valve is also closed. During the time that the valve remains closed the saturated steam in the pipe 4:, condenses to some ex.- tent, so that there is an accumulation of water to be first discharged through the pipes to the engine cylinders when the drifting valve is first opened, and this is an adof pipe 4:, may be increased toprovide additional condensing space for the accumulation of the water.

When the drifting valve is applied to engines using superheated steam, an additional check valve 14, may be employed and be mounted in the same casing with the drifting valve, i desired. When the throttle is open the higher pressure of the superheated steam acting upon the larger top area of said check valve holds the same closed against the lesser pressure of the saturated steam, and prevents any of said saturated steam from flowing into the engine valve chests along with thesuperheated steam even if the-drifting valve 2 should be open at such times. As soon however as the throttle is closed the pressure acting on the top of the check valve 14, is relieved and the pressure of the saturated steam admitted through the open drifting valve .immedisuperheated steam and is admitted to the valve chests only when the throttle is used.

It will now be apparent that we have pro- \"ided a very simple construction in which the How of steam through the drifting valve is positively controlled by the movement of the reverse gear, whereby the same is open at the proper time but closed at other times,

thus making itsaction thoroughly efiicientcylinders when the throttle is closed, and j means operated bythe movement of said reverse gear for actuating-said valve.

3. In a locomotive drifting valve mechanism, the combination with the reverse gear, of a valve for controlling the admission of a limited quantity of steam to the engine cylinders when the throttle is closed, and a cam device'operated by the movement of the reverse gear for actuating said valve.

4, In a locomotive drifting valve mechanism, the combination with the reverse gear, of-a valve for controlling the admission of a limited quantity of steam to the engine cylinders when the throttle is closed, and means operated from the reverse shaft for actuating saidvalve.

5. In a locomotive driftin valve mechanism, the combination with t e reverse gear, of a valve for controlling the admission of a limited quantity ofsteam to the engine .cylinders when the throttle is closed, and-a cam mounted on thereverse shaft a limited quantity of steam tothe engine cylinders when the throttle is closed, and means operated by the movement of the reverse lever to its corner position for permitting the closure-of said valve.

8. In a locomotivedrifti'ng valve mechanism, the combination with the reverse gear, of a valve for controlling the admission of a limited quantity of steam to the engine cylinders when the throttle is closed, and means operated by the movement of the reverse lever to its central position for permit-ting the closure of said valve.

9. In a locomotive drifting valve mechanism, the combination With a valve for controlling the admission of a limited quantity of saturated steam to the engine cylinders, of a check valve device located between said drifting valve and cylinders for closing the passage by the back pressure.

10. In a locomotive drifting valve mechanism, the combination with a valve for controlling the admission of a limited quantity of saturated steam to the enginecylinders,

of a valve means operated by the pressure from the engine valve chest when the throttle is open, for preventing the flow of saturated steam through said drifting valve to the cylinders.

11. In a locomotive drifting valve mechanism, the combination with a valve for controlling the admission of a limited quantity of saturated steam to the engine cylinders,

-of a check valve located between the drifting Valve and cylinders and having a larger area subject to the back pressure than that subject to the saturated steam pressure.

FREDERICK WV. MARTIN. J OIIN L; MOHUN. V

\Vitnesses:

A. I. DENN LLEY, EMILY L. MYERS. 

